We investigated the effects of the Ni : Cu ratio and metal loading of a CeO
2-supported bimetallic Ni–Cu catalyst on its reduction behavior and catalytic performance during steam reforming of ethanol for H
2 production. Compared with monometallic Ni and Cu catalysts, both the NiO and CuO phases in the bimetallic catalysts were reduced at lower temperatures to form fine NiCu alloy crystallites. At a reaction temperature of 673 K, Ni/CeO
2 exhibited a higher H
2 yield than Cu/CeO
2 but also produced a large quantity of CH
4 and carbon deposits. The undesired byproducts were substantially inhibited by replacing a portion of the Ni with Cu. The highest H
2 yield and an excellent carbon inhibition were achieved when the content of each metal was 5 wt%. Notably, a physical mixture of Ni/CeO
2 and Cu/CeO
2, each with the same metal contents, exhibited a lower H
2 yield and heavy carbon deposition. This indicates that the higher reducibility and alloying in the bimetallic catalyst are key factors for synergistic improvements of the catalytic properties.
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